This invention relates to an apparatus for use in testing the efficiency of an air compressor system (consisting of compressor and drive) and as a related aspect a method for the testing of the efficiency of an air compressor. The preferred embodiment of the invention is particularly adapted for on-site testing of air compressors in existing installations.
Pneumatic systems (i.e. compressed air systems) are in widespread use, such as in manufacturing plants and service stations. Compressed air is used as a power source for many applications, such as for penumatic tools and equipment and for pressurizing inflatable devices such as tires and the like.
In many typical installations an air compressor is associated with a compressed air storage tank, and the compressor operates whenever the storage pressure drops below a certain level. By using a storage tank, the compressed air system has an adequate supply available for peak demands, and yet during periods of lower demand, can be replenished by operation of the air compressor. An air compressor is typically sized on the basis of expected demand, and therefore, there is a wide range of compressor sizes in actual use, each one's size depending upon the expected demands for the particular installation.
As is the case for virtually all mechanical devices, continuing usage of an air compressor eventually results in the compressor becoming less efficient. The extent of the inefficiency may not be readily apparent because the increased costs incurred for powering the compressor are often lumped into general power costs for the plant or service station. In other words, while a compressor may continue to perform adequately, the power input to run the compressor may progressively increase with time and in this way constitute a significant hidden cost of operating the plant or service station.
The present invention is directed to a novel apparatus for testing of the efficiency of an air compressor system, and it has the particular advantage of not requiring the compressor to be disconnected and transported to a test facility. In other words the testing can be done on-site and simply involves connecting the test apparatus in the on-site installation and then running the compressor for a brief amount of time to acquire information sufficient to calculate the efficiency of the compressor system. On the basis of the information obtained through use of the test apparatus, a calculation of the compressor's efficiency is made. The owner of the compressor can then decide whether the efficiency has become low enough to warrant replacement or rebuilding of the compressor.
In addition to the ability of the present invention to provide on-site testing of a compressor, a single test apparatus is adapted to testing a wide range of compressor sizes. Moreover, the apparatus can be used regardless of the type of power used to drive the compressor. Typical compressors are driven either by electric motors or by gas powered engines. Therefore the power input to a compressor during the test procedure can be readily ascertained by measuring either the electric power input in the case of an electric motor driven compressor or by the fuel input to the engine in the case of an engine driven compressor.
The apparatus of the present invention also has the advantage that it can be fabricated entirely from standard parts and/or parts which can be readily fabricated. The preferred embodiment of the invention disclosed herein comprises a number of shut-off valves, pipes and fittings, all standard parts, and it also includes a set of orifice plates which can be readily fabricated.
The foregoing features, advantages and benefits of the invention, along with additional ones, will be seen in the ensuing description and claims which should be considered in conjunction with the accompanying drawings. The drawings disclose a preferred embodiment of the invention according to the best mode contemplated at the present time in carrying out the invention.